Illustrative image, not evidence of a product test.
Best Smart Radiator Valves for Europe (2026)
Short answer: a smart radiator valve (TRV) changes one radiator. It does not, by itself, tell your boiler to fire. Before choosing a brand, settle three things: whether your existing valves are thermostatic, whether you need the boiler to respond to the valves, and which hub or Thread border router you will use. Brand comes after that.
This is a documentation-based comparison, not a HomeTechTested lab test. Specifications, requirements and prices come from manufacturer pages and support documents checked on 22 Oct 2026. We do not measure accuracy, battery life or energy savings.
Three checks before you buy
- Valve type. Smart heads replace the head on a thermostatic radiator valve. Aqara states manual valves, return-temperature limiters and monotube systems are not supported (Aqara). tado makes the same distinction (tado support).
- Boiler response. Which? explains that valves work locally on each radiator, while a smart thermostat decides whether the boiler is on or off (Which?). If no room thermostat or receiver calls for heat, valves only restrict flow.
- Controller. Every option below needs something besides the valve: a bridge, a Thread border router or a hub.
Does it call for heat from your boiler?
| Valve | Can it switch the boiler? | What the documentation says |
|---|---|---|
| tado° Smart Radiator Thermostat X | Only with a tado° thermostat or receiver | With tado° also controlling the boiler, valves sync with the central Smart Thermostat so each room can request heat (tado shop). Without boiler access, tado describes a valves-only setup (tado support). |
| tado° V3+ Add-on Radiator Thermostat | Same principle, V3+ line only | Needs the V3+ Internet Bridge; X and V3+ cannot share a tado° Home (tado support). |
| Eve Thermo (5th gen) | No Eve boiler option found | Eve’s Thermostat product supports water-based underfloor heating only, not boilers or heat pumps (Eve). The Thermo page describes valve-level control only. |
| Netatmo Radiator Valve ORIGINAL | Documented for the Netatmo thermostat line | Sold as compatible with the Wired or Wireless Thermostat ORIGINAL (Netatmo EU). On the previous generation, Netatmo said valves paired with a thermostat can start heating, while a Starter Pack relay (district heating) cannot (Netatmo help). |
| Aqara Radiator Thermostat E1 | No boiler function documented | Aqara’s pages describe valve control, schedules and window detection only. |
| Meross MTS150-series | No boiler function documented | Not verified. |
Controller and ecosystem dependencies
| Valve | You must also have | Radio | Subscription | Platforms stated by the manufacturer |
|---|---|---|---|---|
| tado° X | tado° Bridge X, or a compatible Thread border router that supports NAT64 (tado support) | Thread / Matter | Free app; paid AI Assist, €3.99 or £3.99 per month, adds geofencing, adaptive heating and advanced open-window detection | Alexa, Google Assistant, Apple Home |
| tado° V3+ | V3+ Internet Bridge | tado° V3+ platform | Auto-Assist €3.99/month or €29.99/year (tado shop) | Alexa, Google Assistant, Apple HomeKit |
| Eve Thermo (5th gen) | Matter controller plus Thread border router (Eve) | Thread / Matter | None; Eve states no subscription or registration | Apple Home, SmartThings, Alexa, Home Assistant, Google Home |
| Netatmo ORIGINAL | Netatmo thermostat; Thermo Hub sold separately for Matter | Not stated on the page read | None listed on the page read | Matter via Thermo Hub: Apple Home, Google Home, Alexa, SmartThings (Netatmo) |
| Aqara E1 | An Aqara Zigbee 3.0 hub (Aqara) | Zigbee 3.0 | None listed | Apple HomeKit, Alexa, Google, IFTTT, Alice |
| Meross MTS150 | A Meross hub (Meross FAQ) | One independent review reports 433 MHz RF to the hub (NotEnoughTech) | None listed | HomeKit stated by Meross; others unverified |
Meross is not a no-hub Wi-Fi valve: Meross’s own documentation says the radiator thermostat pairs through its smart hub. Newer Meross models were not verified for EU/UK.
Valve-fit checklist
- Is the existing head thermostatic (it has a pin and spring), not a manual wheel?
- Is the thread M30×1.5, or do you need an adapter? Photograph the valve body before ordering.
- Are the valves free of leaks, rust and calcification? tado also says not to fit its X head where leak stoppers or corrosion inhibitors are used, or where flow temperature is 85 °C or higher (tado support).
- Do the adapters in the box match your valve? They differ by brand:
| Valve | Thread and adapters in the box |
|---|---|
| tado° X | M30×1.5; set of 6 adapters (tado shop) |
| Eve Thermo | M30×1.5; Danfoss RA, RAV, RAVL only (Eve) |
| Aqara E1 | M30×1.5; RA/RAV/RAVL adapters (Aqara specs) |
| Netatmo ORIGINAL | Six adapters; which ones is not listed on the page read. Extra packs are sold for Danfoss, Caleffi, Giacomini, M28 and M30×1 (Netatmo EU) |
| Meross MTS150HHK (EU kit) | Meross’s store listing, as indexed, names RA, RAV, RAVL, Giacomini, Caleffi and M28×1.5 adapters; the page could not be reopened |
Picks
tado° X: best fit if you also want to control the boiler. tado’s current line is the X range, which uses Thread and Matter; V3+ is still sold, but the two cannot be mixed in one home (tado support). The X head uses a rechargeable USB-C battery pack; tado says it charges in about two hours and needs charging about once a year. Schedules are stored on the device and keep running offline. tado says X is compatible with a smaller range of modulating boilers than V3+, so check your boiler first. List prices on 22 Oct 2026: €99.99 (Austria store) or £79.99 (UK store) per head, with a Halloween promotion showing €59.99 / £59.99. Bridge X was €69.99 list. Prices vary by country (the Finland store showed €64.99 for the head).
Eve Thermo (5th gen): best for Matter and no subscription. Eve states it needs a Matter controller and Thread border router, uses two AA batteries and needs no subscription or Eve cloud. On-device schedules require the Eve app on iPhone/iPad (Apple Home) or Android (Google Home); Eve says on-device schedules are not currently supported through Alexa or SmartThings. Eve’s press release gave €79.95 at launch in Dec 2025; the current store price and UK availability were not confirmed. The current specification lists Thread as the wireless connection (no Bluetooth).
Netatmo Radiator Valve ORIGINAL: for a Netatmo thermostat setup. Netatmo’s EU store lists the valve at €59.99, the valve plus Thermo Hub at €119.99 and the Wired Thermostat ORIGINAL at €139.99. Its geolocation feature sends an alert if you leave without lowering the heating; the page does not describe it as automatic. UK availability of the ORIGINAL valve was not confirmed, and Netatmo’s UK store showed an out-of-stock Smart Thermostat when checked.
Aqara Radiator Thermostat E1: for existing Aqara/Zigbee homes. Aqara specifies 2×AA batteries and says battery life “can last up to one year”, varying with usage, plus geofencing through Aqara Home and window detection that can be linked to its door/window sensor. Aqara also says an Aqara Zigbee 3.0 hub is required. Use with a third-party Zigbee coordinator is not a path Aqara documents. A UK retailer listing showed £54.98 inc. VAT on 22 Oct 2026 (a single-retailer snapshot); an official EU price was not confirmed.
Meross MTS150-series: cheap on paper, verify before buying. The EU MTS150HHK kit is listed with a bundled hub that connects up to 16 valves (Meross store listing as indexed; the page could not be reopened). Meross’s FAQ confirms hub pairing. Current EU/UK pricing, battery life and newer models were not verified, so check the current listing.
What the savings evidence supports
No single percentage applies to every home, and no independent source for a universal 15–25% figure was found. What the sources support:
- tado states an average 22% saving and offers a refund under its Energy Savings Promise for X heating products bought on or after 2 Sep 2026 (used for at least six months, returned within 12 months) (tado). That is a manufacturer claim and a money-back offer, not an independent result.
- The Energy Saving Trust says installing and using heating controls effectively could save around £100 a year in Great Britain (Energy Saving Trust). This covers programmers, thermostats and TRVs together and is a UK figure.
- Which? says manufacturers’ estimates usually assume you previously held a constant temperature. If you already turn heating off when out, you are unlikely to save as much, and in a poorly insulated home insulation comes first. It also notes one or two radiators gain little (Which?).
Limitations
- Prices are single-store snapshots and include promotions. Check your country’s store.
- Battery runtimes quoted here are manufacturer figures, not measured.
- Meross and Netatmo (battery, protocol, UK stock) are the least verified entries.
- Which? says it tested 29 valves, including Hive, Tado and TP-Link; its scores are behind a paywall and not reproduced here.
Alternatives
Which? names Hive, Drayton, Honeywell, TP-Link and Worcester Bosch among brands it tested or asked about support, and says most valves only work with a matching brand’s thermostat. If you already own a boiler-brand thermostat, a same-brand valve may be a better fit than anything above. See our guides to the best smart thermostat, smart home hubs and smart home ecosystems.
FAQ
How long do the batteries last?
Manufacturers differ. Aqara says up to one year, varying with usage. tado says its X head’s rechargeable pack needs charging about once a year. Eve lists two AA batteries without a life figure on the page read. Treat all figures as claims.
Will a smart head fit any radiator?
No. It must be a thermostatic valve, and adapters differ by brand (see the table above).
Can I mix brands?
Different radios and apps mean separate systems. Matter may let some devices share a platform, but boiler control and features stay within each brand.
Do I need a smart thermostat as well?
For valves to call for heat, yes: use a thermostat or receiver from the same ecosystem (tado, or Netatmo’s thermostat line).
What happens offline?
tado says X schedules run offline because they are stored on the device. Eve says the same for Eve Thermo schedules. Offline behaviour for the others was not verified.
Research method: manufacturer pages, support articles and manuals checked 22 Oct 2026, plus Which? and the Energy Saving Trust for independent context. See how we compare products.